Today in most of electronic cigarette and electronic cigarette case, a microcontroller is directly supplied electric power by a battery, the microcontroller powers on or off a load via controlling a switch field effect transistor (hereinafter, referred to as “MOSFET”), as shown in FIGS. 1 and 2, a circuit of the electronic cigarette contains a battery 100, a microcontroller 200 and a field effect transistor 300, wherein battery 100 is used to supply electric power to both microcontroller 200 and the load, microcontroller 200 is used to output a control signal to turn on or off the field effect transistor 300 for controlling the heating element of the electronic cigarette and electronic cigarette case. There are some risks of the power supply structure of FIGS. 1 and 2, such as, when the MOSFET is turned on and if the load circuit is in short circuit or over current condition, an output voltage of the battery applied as a supply voltage of the microcontroller drops rapidly, further in case that the supply voltage of the microcontroller drops below minimal operating voltage of the microcontroller, the microcontroller becomes uncontrollable or unstable state. The internal components and wires of the electronic cigarette may be damaged by excess current caused by the over current or short circuit.
The uncontrollable state of the microcontroller may lead to other unexpected damage, so it is necessary to develop a circuit to delay the supply voltage of the microcontroller dropping.
Therefore, the existing technology has flaws, and needs to be improved.